With the temperatures just above zero, and the chances to learn something meaningful therefore limited, there was minimal running in the early stages. But as the clock ticked towards lunch the action picked up, with McLaren’s Stoffel Vandoorne setting the pace after a run on Pirelli’s new hypersoft tyres.
But shortly before 1.00pm local time Bottas, with soft tyres bolted to his Mercedes, bettered the Belgian’s effort by 0.055s as he upped his morning lap tally to 43 – the most of anyone.
Ferrari’s Sebastian Vettel, who like Vandoorne was making his first appearance of pre-season, got 30 laps under his belt as he went third quickest on medium rubber, with Renault’s Carlos Sainz a little further back in fourth place.
F1 newcomers Sergey Sirotkin and Charles Leclerc both managed more than 35 laps for Williams and Sauber respectively, while at the other end of the scale Haas’s Kevin Magnussen and Red Bull’s Max Verstappen spent the majority of the morning in the garage, the latter failing to log a lap time after a spin and what the team described as 'a minor fuel leak'.
Nico Hulkenberg, Lewis Hamilton and Robert Kubica were all due to take turns behind the wheel in the afternoon for Renault, Mercedes and Williams respectively, with the lunch break cancelled to allow for more track running. However, the Silver Arrows later confirmed that Bottas would remain in the cockpit of the W09 to maximise mileage after limited morning running.
You can follow minute-by-minute Live Timing from pre-season testing on the Official F1 App. For more information, click here.